Molding core

Abstract

A molding core includes: a core body having an article-shaping surface; and a hard coating formed on the article-shaping surface of the core body and including a diamond-like carbon film that includes carbon, oxygen, and at least one bonding-enhancing element which is selected from silicon, titanium, aluminum, tungsten, tantalum, chromium, zirconium, vanadium, niobium, hafnium, and boron, and which forms covalence bonding with the carbon and the oxygen.

1 . A molding core useful for molding a glass, comprising: 
 a core body having an article-shaping surface; and    a hard coating formed on said article-shaping surface of said core body and including a diamond-like carbon film that comprises carbon, oxygen, and at least one bonding-enhancing element which is selected from the group consisting of silicon, titanium, aluminum, tungsten, tantalum, chromium, zirconium, vanadium, niobium, hafnium, and boron, and which forms covalence bonding with the carbon and the oxygen.    
   
   
       2 . The molding core of  claim 1 , wherein said diamond-like carbon film comprises crystalline nano-particles of a carbide of said bonding-enhancing element and crystalline nano-particles of an oxide of said bonding-enhancing element dispersed therein.  
   
   
       3 . The molding core of  claim 1 , wherein said bonding-enhancing element is silicon.  
   
   
       4 . The molding core of  claim 3 , wherein said hard coating further includes an intermediate film sandwiched between said core body and said diamond-like carbon film.  
   
   
       5 . The molding core of  claim 4 , wherein said intermediate film includes a composite layer of a silicon carbide formed on said article-shaping surface of said core body.  
   
   
       6 . The molding core of  claim 5 , wherein said composite layer has a thickness ranging from 50 to 100 nm.  
   
   
       7 . The molding core of  claim 6 , wherein said intermediate film further includes an amorphous carbon layer that is sandwiched between said composite layer and said diamond-like carbon film and that comprises carbon, oxygen, and silicon which forms covalence bonding with the carbon and the oxygen.  
   
   
       8 . The molding core of  claim 7 , wherein said amorphous carbon layer comprises crystalline nano-particles of a silicon carbide and crystalline nano-particles of a silicon oxide dispersed therein.  
   
   
       9 . The molding core of  claim 8 , wherein said amorphous carbon layer has a thickness ranging from 50 to 100 nm.  
   
   
       10 . The molding core of  claim 1 , wherein said diamond-like carbon film has a thickness ranging from 100 to 150 nm.  
   
   
       11 . The molding core of  claim 1 , wherein said core body is made from a material selected from the group consisting of tungsten carbide, silicon carbide, and silicon oxide.